////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
////////////////////////////////////////////////////////////////////////////////

#ifndef ARANGOD_ACTIONS_ACTIONS_H
#define ARANGOD_ACTIONS_ACTIONS_H 1

#include <functional>
#include <memory>
#include <string>

#include "Basics/Common.h"
#include "Basics/Mutex.h"

struct TRI_vocbase_t;

namespace arangodb {
class GeneralRequest;
class GeneralResponse;
}  // namespace arangodb

/// @brief action result
class TRI_action_result_t {
 public:
  TRI_action_result_t() : isValid(false), canceled(false) {}

  bool isValid;
  bool canceled;
};

/// @brief action descriptor
class TRI_action_t {
 public:
  TRI_action_t() : 
    _urlParts(0), 
    _isPrefix(false), 
    _allowUseDatabase(false),
    _isSystem(false) {}

  virtual ~TRI_action_t() = default;

  virtual void visit(void*) = 0;

  virtual TRI_action_result_t execute(TRI_vocbase_t*, arangodb::GeneralRequest*,
                                      arangodb::GeneralResponse*,
                                      arangodb::Mutex* dataLock, void** data) = 0;

  virtual void cancel(arangodb::Mutex* dataLock, void** data) = 0;

  void setUrl(std::string const& url, size_t urlParts) {
    _url = url;
    _urlParts = urlParts;
  }

  std::string _url;

  size_t _urlParts;

  bool _isPrefix;
  bool _allowUseDatabase;
  bool _isSystem;
};

/// @brief fake action class used only inside /_admin/execute RestHandler 
class TRI_fake_action_t final : public TRI_action_t {
 public:
  TRI_fake_action_t(std::string const& url, size_t urlParts) 
      : TRI_action_t() {
    setUrl(url, urlParts);
  }

  void visit(void*) override {}

  /// @brief actions of this type are executed directly. nothing to do here
  TRI_action_result_t execute(TRI_vocbase_t*, arangodb::GeneralRequest*,
                              arangodb::GeneralResponse*,
                              arangodb::Mutex*, void**) override;

  /// @brief actions of this type are not registered anywhere, and thus
  /// cannot be canceled
  void cancel(arangodb::Mutex*, void**) override {}
};

/// @brief defines an action
std::shared_ptr<TRI_action_t> TRI_DefineActionVocBase(std::string const& name,
                                                      std::shared_ptr<TRI_action_t> action);

/// @brief looks up an action
std::shared_ptr<TRI_action_t> TRI_LookupActionVocBase(arangodb::GeneralRequest* request);

/// @brief deletes all defined actions
void TRI_CleanupActions();

/// @brief visit all actions
void TRI_VisitActions(std::function<void(TRI_action_t*)> const& visitor);

#endif